Module: Cms::Settings

Extended by:
Settings
Included in:
Settings
Defined in:
lib/bcms_settings/cms/settings.rb

Defined Under Namespace

Classes: CmsModuleProxy, InvalidModuleName, ModuleConfigurationExists, ModuleNotRegistered

Instance Method Summary collapse

Dynamic Method Handling

This class handles dynamic methods through the method_missing method

#method_missing(method_id, *args) ⇒ Object

This method_missing implementation enables client code to call arbitrary methods on the Settings module. Undefined methods whose name does not conform to BCMS’s module naming convention are handled elsewhere (presumably rasing a NoMethodError exception)

If a module with name equal to the called method has been registered previously, a module method with the same name is defined (so it does not go through method missing again) and a proxy object is returned.

If the module has not been registered previously, a ModuleNotRegistered exception is raised.

Given: Cms::Settings.modules => [“bcms_s3”, “bcms_seo_sitemap”]

Cms::Settings.bcms_s3 => #<Cms::Settings: bcms_s3 => “account_id”=>“NEW_ID” Cms::Settings.bcms_news => ModuleNotRegistered Cms::Settings.foo => NoMethodError



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# File 'lib/bcms_settings/cms/settings.rb', line 149

def method_missing(method_id, *args)
  method_name = method_id.to_s
  unless method_name =~ CmsModule::NAME_REGEX
    super(method_id, *args)
  end
  define_method(method_name) do
    CmsModuleProxy.new(find_module(method_name))
  end
  send(method_name)
end

Instance Method Details

#delete(module_name) ⇒ Object

Destroys the CmsModule object. Trying to delete a module that has not been registered raises an exception:

Cms::Settings.modules => [“bcms_s3”, “bcms_seo_sitemap”] Cms::Settings.delete(“bcms_news”) => ModuleNotRegistered

At the moment it is possible to delete cms managed modules although they will be automatically registered again if Cms::Settings.synchronize is called.



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# File 'lib/bcms_settings/cms/settings.rb', line 126

def delete(module_name)
  remove_modules [module_name.to_s]
end

#modules ⇒ Object

Retruns an array of module names the Cms::Settings module knows about.

in environment.rb

gem.bcms_s3 gem.bcms_news

Cms::Settings.modules => [“bcms_s3”, “bcms_news”] Cms::Settings.register(“bcms_blog”) Cms::Settings.modules => [“bcms_s3”, “bcms_news”, “bcms_blog”]



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# File 'lib/bcms_settings/cms/settings.rb', line 61

def modules
  registered_modules
end

#register(module_name) ⇒ Object

Manually registered modules are ignored by the synchronize method.

Cms::Settings.register(“bcms_foo”) Cms::Settings.bcms_foo will be prsisted in the the database until manually deleted.

Manually registered module names must conform to BCMS’s module naming conventions, so this call will raise an InvalidModuleName exception: Cms::Settings.register(“foo”) => InvalidModuleName

Modules can only be registered once: Cms::Settings.modules => [“bcms_s3”, “bcms_seo_sitemap”] Cms::Settings.register(“bcms_s3”) => ModuleConfigurationExists

****************** **IMPORTANT NOTE** ****************** When developing modules that use the Settings API, it is necessary to register them manually since they can’t declare themselves as dependencies. This can be done in an initializer, however, since modules can only be registered once, every time the modules’ project boots, an exception will be raised.

One possible workaround is to check if the module is registered already:

unless Cms::Settings.modules.include?(‘bcms_seo_sitemap’)

Cms::Settings.register('bcms_seo_sitemap')

end

A marginally better approach would be something like:

unless Cms::Settings.registered?(‘bcms_seo_sitemap’)

Cms::Settings.register('bcms_seo_sitemap')

end

Another possibility is to have the register method fail silently if the module already exists or just log a warning.

I do like the exceptions approach because it makes it evident that somehow, somewhere, for some reason, someone registered that module previously and may be using the configuration object for something.

This is particularly important because in reality, ‘registered modules’ need not to even be modules at all. Someone may just register ‘bcms_my_configuration’ for whatever purpose even from the console.



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# File 'lib/bcms_settings/cms/settings.rb', line 111

def register(module_name)
  register_modules [module_name], false
end

#synchronize ⇒ Object

cms managed modules are those that are declared as dependencies on environment.rb. The synchronize method keeps these installed modules in sync with the database automatically, creating a record for declared dependencies and deleting records for bcms_modules that are no longer installed.

Cms::Settings.synchronize can be called as part of BrowserCMS’ initialization process.

If this method is never called, there won’t be any cms managed ‘automatic’ modules, in which case all modules must register themselves calling Cms::Settings.register(“bcms_xyz”) ‘ Conversely, if this method is called, all installed bcms modules will get a configuration object whether they need it or not.



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# File 'lib/bcms_settings/cms/settings.rb', line 43

def synchronize
  if CmsModule.table_exists?
    register_modules(installed_modules - registered_modules)
    remove_modules(managed_modules - installed_modules)
  end
end